Head and back rest component for dental chairs



p 21, 1965 K. c. KERR 3,207,555

HEAD AND BACK REST COMPONENT FOR DENTAL CHAIRS Filed April 8, 1963 FIG. I

2 Sheets-Sheet 1 IN V EN TOR.

ATTORNEY K. c. KERR 3,207,555

HEAD AND BACK REST COMPONENT FOR DENTAL CHAIRS Sept. 21, 1965 2 Sheets-Sheet 2 Filed April 8, 1965 INVENTOR.

KENN

ET; C. KERR FIG. 2

ATTORNEY United States Patent 3,207,555 HEAD AND BACK REST COMPONENT FOR DENTAL CHAIRS Kenneth C. Kerr, 1222 S. Riverside, Medford, Oreg. Filed Apr. 8, 1963, Ser. No. 271,407 6 Claims. (Cl. 297391) This invention relates to a head and back rest component for dental chairs, and comprises an improvement over the structure shown in my co-pending application Serial No. 251,130, filed January 14, 1963, for Dental Chair Component, now Patent No. 3,156,500, granted November 10, 1964.

A primary objective of the present invention is to provide an improved head and back rest component for dental chairs which is particularly useful for supporting I the head and back of a patient in a lay-down position.

Another object of the present invention is to provide a head and back rest component for dental chairs which has means for inclining the head rest relative to the back rest whereby to accommodate patients of different physical shapes and sizes.

Another object is to provide a head rest and back rest for dental chairs having a novel arrangement of parts wherein the head rest is adapted to be inclined relative to the back rest and wherein hardware for accomplishing such movement is principally concealed and in an out-ofthe-way position.

The invention will be better understood and additional objects thereof will become more apparent from the accompanying specification and claims considered together with the accompanying drawings, wherein like numerals of reference indicate like parts, and wherein:

FIGURE 1 is a side elevational view of a dental chair employing the present head and back rest component and showing a patient supported therein and a dentist in working condition;

FIGURE 2 is a top plan view of the present component with parts thereof broken away for clarity;

FIGURE 3 is a fragmentary longitudinal sectional view thereof taken on the line 3-3 of FIGURE 2;

FIGURE 4 is a transverse sectional view taken on the line 4-4 of FIGURE 2;

FIGURE 5 is a fragmentary sectional view taken on the line 55 of FIGURE 3; and

FIGURE 6 is an end elevational view taken from the head end of the component.

Referring now in particular to the drawings, and first to FIGURE 1, the component of the present invention is utilized with a dental chair of the type employing a base 10 on which is supported a seat 12 and arm rest 14. Pivotally connected to the base 10 are back rest supporting brackets 16 which are pivotally adjustable to various positions relative to the base, comprising upright and horizontal positions or any position therebetween. Structural details for adjusting the back rest supporting brackets 16 are not shown since such structure is conventional.

The present component is intended for use primarily in conditions wherein the patient assumes a lying down position and the dentist assumes a seated position while working thereon, as illustrated in FIGURE 1. It is to be understood, however, that the present component in its design also functions efiiciently as a back and head rest for a patient in a sitting position.

The present component comprises a head rest 20, FIGURES 1-3, a back rest 22, and a pivot housing or pivot box 24.

Head rest 20 employs a laterally contoured rigid frame element 26, FIGURE 3, which supports padding 28, this head rest structure being suitably covered with covering material 30. As best seen in FIGURE 6, the transverse contour of the head rest is such as to provide a comfortable and efiicient support for a patients head.

Back rest 22 has a rigid frame element 34, FIGURES 2, 3, and 5, and similar to the head rest has suitable padding 36 and decorative covering 37, FIGURE 3. The forward end of rigid frame element 34 has an integral tapered extension 38 provided with a transverse slot 40, FIGURES 3, 4 and 5, intermediate its ends, the slot being foreshortened relative to the width of the extension and having a front upper projection 40a.

Secured integrally to the rigid frame element 34 and extension 38, as by bolts or screws 41, are upper and lower reinforcing plates 42 and 44, respectively. As best seen in FIGURE 5, the forward end of plates 42 and 44 are narrower than the extension 38 to form shoulders 46 on opposite sides of the said extension.

The pivot housing 24 is seated on the extension 38 and has side walls 50 which engage the shoulders 46 of the extension 38, a rear wall 52, and a laterally contoured top wall 54. As seen in FIGURE 3, the pivot housing 24 has a front wall 56 provided with an opening 58. The upper portion of the housing 24 has padding 60, and such housing has a suitable covering 62. The housing 24 is securely attached to the extension 38 by screws 64 projecting through the extension and engaged with the side walls 50.

Mounted transversely in the housing 24 adjacent the front thereof is a hinge 70. One leaf 72 of the hinge is secured to the extension 38 by bolts 74 and has a slotted portion 76 therein. The other leaf 78 is secured to a right angle lever arm 80, as by welding, one end of which projects forwardly through the opening 58 in the front wall 56 of the housing, FIGURE 3, and is pivotally attached by means of a transverse shaft 82 mounted in lugs 84 integrally attached to the head rest 20.

The end of lever arm which is disposed in the housing 24 is secured, as by welding, to a pair of spaced sleeves 86 rotatably supporting a shaft 88. Shaft 88 has a threaded diametral bore 90 threadedly receiving a drive screw 92 intermediate the sleeves 86 and projecting downwardly through the slot 76 in the hinge leaf 72 and through the slot 40 in the extension 38. In this regard each of the reinforcing plates 42 and 44 is slotted in the area of the slots 40 and 76 to allow the screw 92 to project therethrough, such slots being designated by the numeral 94 and being of a less transverse dimension than the transverse dimension of slot 40.

The projecting or free end of drive screw 92 carries a turning handle 96 and an integral collar 98 spaced thereabove. A pivot shaft 100 is disposed in slot 40 and is mounted on the drive screw 92 by means of a diametral bore receiving such screw. This shaft is confined in the slot 40 by the upper and lower reinforcing plates 42 and 44, and although the shank of screw 92 is slidable through the shaft 100, axial movement of the screw is substantially restricted by the handle 96 and collar 98.

A decorative plate 102 is mounted on the forward end of extension 38 and is suitably slotted at 104 to receive the adjacent portion of handle 96.

By the arrangement provided the screw 92 is axially stationary, and upon rotation thereof it pivots the arm 80 on the hinge 70 to vary the inclination of the head rest 20 relative to the back rest. That is, by turning the handle 96 in a right hand direction the screw 92 exerts a downward pulling force on shaft 88 to pivot the arm 80 and head rest upwardly. In rotating the handle 96 in a left hand direction the head rest is lowered. FIG- URE 3 illustrates in dotted lines an upper inclined position of the head rest and pivot mechanism.

In the lowered position of the head rest, the screw is forwardly inclined, as shown, and it is the purpose of slot projection 40a to receive the collar 98 and permit such forwardinclination. In addition, the slots 94 and 104 in the plates 44 and 102, respectively, may be enlarged to permit the handle to work therein in forwardly inclinedpositions of the screw 92.

Thus, inclination of the head rest may be varied to accommodate varying physical shapes and sizes of patients, as well as to accommodate head positions for convenience of the dentist. Through means of the pivot housing 24, the pivot mechanism is concealed, and except for the turning handle is in a complete out-of-the-way position.

It is to be understood that the form of my invention herein shown and described is to be taken as a preferred example of the same and that various changes in the Shape, size and arrangement of parts may be resorted towithout departing from the spirit of my invention or the scope of the subjoined claims.

Having thus described my invention, I claim:

1. A dental chair component comprising a back rest, a head rest pivotally attached to said back rest, and a drive screw threadedly engageable with one of said back rest and head rest and being confined in the other of said back rest and head rest to restrict axial movement of the drive screw whereby upon rotation of said screw said head rest is driven pivotally relative to said back rest.

2. A dental chair component comprising a back rest, a housing integrally secured to one end of said back rest, a head rest pivotally attached to said housing, and a drive screw threadedly engageable with one of said housing and head rest and being confined in the other of said housing and head rest to restrict axial movement of the drive screw whereby upon rotation of said screw said head rest is driven pivotally relative to said housing.

3. The dental chair component of claim 2 wherein said back rest and head rest have patient supporting surfaces and said housing has a patient supporting surface in the same general plane as the patient supporting surfaces of said back rest and head rest.

4. A dental chair component comprising a back rest, a head rest,.and' pivotal interconnecting means disposed between said back rest and said head rest, said pivotal interconnecting means comprising a hinge having one leaf thereof secured to said back rest and the other leaf thereof connected to one end of a lever arm, the other end of said lever arm being connected to said head rest, and a drive screw operably connected to said lever arm for rotating the latter on said hinge to vary the inclination of said head rest relative to said back rest.

5. The dental chair component of claim 4 wherein said back rest has a'transverse slot and said drive screw passes therethrough, and transverse shaft means on said drive screw restricting axial movement of the latter.

6. The dental chair component of claim 4 wherein said back rest has a transverse slot and said drive screw passes therethrough, a turning handle on said drive screw, a fixed collar on said drive screw spaced from said handle, and a transverse shaft on said drive screw intermediate the handle and collar and confined in said slot to restrict axial movement of the drive screw.

References Cited by the Examiner UNITED STATES PATENTS FRANK B. SHERRY, Primary Examiner. 

1. A DENTAL CHAIR COMPONENT COMPRISING A BACK REST, A HEAD REST PIVOTALLY ATTACHED TO SAID BACK REST, AND A DRIVE SCREW THREADEDLY ENGAGEABLE WITH ONE OF SAID BACK REST AND HEAD REST AND BEING CONFINED IN THE OTHER OF SAID BACK REST AND HEAD REST TO RESTRICT AXIAL MOVEMENT OF THE DRIVE SCREW WHEREBY UPON ROTATION OF SAID SCREW SAID HEAD REST IS DRIVEN PIVOTALLY RELATIVE TO SAID BACK REST. 